1. Field of the Invention
The present invention relates to a multiphase connector having a plug connector and a receptacle connector with improved lock means for locking the plug connector to the receptacle connector.
2. Description of the Related Art
Patent Reference 1 has disclosed a conventional multiphase connector. As shown in FIG. 8 to FIG. 12, the conventional multiphase connector has a connector C1 and a mating connector C2. The connector C1 is formed of a connector main body 100, a sleeve 110, and a spring member 120. The connector main body 100 has a connector engaging portion 101 at a distal end thereof. The connector engaging portion 101 is provided with a spring receptacle seat 102 with a circular shape; a projecting portion 103 extending along a direction that the connector is inserted and pulled out; and a step portion 105 on an outer circumference thereof. The connector engaging portion 101 is also provided with a projecting portion 104 at one position in a circumference direction.
The sleeve 110 is provided with a recess portion 112 at one position in a circumference direction of an edge portion 111 thereof. The recess portion 112 has a lateral width larger than a lateral width of the projecting portion 104. The sleeve 110 is also provided on an inner circumferential side of a front end portion thereof with a guide groove 115 extending between a front end surface of the sleeve 110 and a starting portion of a guide surface 114 of a long hole 113. The sleeve 110 engages the engaging portion 101 to be rotatable. The spring member 120 is disposed between the edge portion 111 of the sleeve 110 and the spring receptacle seat 102. A positioning mechanism is formed of the projecting portion 104 and the recess portion 112.
When the sleeve 110 moves backward and the projecting portion 104 engages the recess portion 112, a gap is formed as a play space between the projecting portion 104 and the recess portion 112, so that the sleeve 110 is allowed to rotate within a specific angle in the play space. When the projecting portion 104 engages the recess portion 112, as shown in FIG. 9, the sleeve 110 abuts against the step portion 105, so that a retraction position of the sleeve 110 is restricted and the position becomes an initial position of the sleeve 110.
As shown in FIG. 9, the mating connector C2 has an engagement portion 121 with a cylindrical shape. The engagement portion 121 is provided with outward projecting portions 123 at two positions in a circumferential direction separated by 180 degrees. The engagement portion 121 is also provided with a long groove portion (not shown) extending in the direction that the connector is inserted and pulled out.
An engaging mechanism is formed of the projecting portion 103 of the connector C1 and the groove portion of the mating connector C2. The engaging mechanism restricts an engaging position of the engaging portion 101 of the connector C1 and the engagement portion 121 of the mating connector C2 in the circumferential direction. After the projecting portion 103 of the connector C1 is positioned in the groove portion of the mating connector C2, when the engaging portion 101 is inserted and engages the engagement portion 121 of the mating connector C2, the outward projecting portions 123 of the mating connector C2 are inserted into the long holes 113 of the sleeve 110 through the guide grooves 115 to be guided into the starting portions of the guide surfaces 114 as shown in FIG. 9. At this time, even if the sleeve 110 idly rotates at the initial position, the outward projecting portions 123 of the mating connector C2 are guided into the starting portions of the guide surfaces 114 with the guide grooves 115.
A locking operation is performed through rotating the sleeve 110. That is, after the both connectors C1 and C2 are connected, when the sleeve 110 is rotated in an arrow direction R, the outward projecting portions 123 push the guide surfaces 114 in a forward direction, so that the sleeve 110 moves forward while rotating against an urging force of the spring member 120. Accordingly, after the engaging position of the guide surfaces 114 and the outward projecting portions 123 moves through a state shown in FIG. 10, the long holes 113 engage the outward projecting portions 123, thereby achieving a locked state as shown in FIG. 11 and FIG. 12.
When the locking operation is performed as described above, if the sleeve 110 is situated at the initial position, the recess portion 112 is situated at the projecting portion 104 of the positioning mechanism. Accordingly, it is impossible to rotate the sleeve 110 beyond a range of the idle rotation described above while the sleeve 110 is situated at the initial position.
When the both connector C1 and C2 are connected, the outward projecting portions 123 of the mating connector C2 are guided into the starting portions of the guide surfaces 114. Accordingly, when the sleeve 110 is rotated, the outward projecting portions 123 slide along the guide surfaces 114 to move the sleeve 110 forward. When the sleeve 110 is moved forward, the projecting portion 114 moves out from the recess portion 112 of the positioning mechanism, so that the sleeve 110 is released from the restricted state (positioned state) with respect to a rotational angle thereof. As a result, after the both connectors C1 and C2 are connected, it is possible to lock just through rotating the sleeve 110.
Patent Reference 2 has disclosed a conventional multiphase connector. As shown in FIG. 13 and FIG. 14, a coupling nut 201 is rotatably attached to a plug 200. A pair of engaging pins 202 is disposed on an inner circumferential surface of the coupling nut 201. In this case, it is arranged such that the coupling nut 201 does not move relative to a barrel 203 in a direction that the connector is inserted and pulled out. A pair of cam grooves 212 with a substantially L shape is disposed on an outer circumferential surface of a shell 211 of a receptacle 210.
When a plug 200 linearly engages the receptacle 210 in an arrow direction as shown in FIG. 14, each engaging pin 202 abuts against and is guided with an introducing portion of each cam groove 212, so that the coupling nut 201 rotates by a certain angle. Then, the coupling nut 201 rotates in an opposite direction with a restoration force of a torsion coil spring (not shown) disposed in the plug 200 with both ends fixed, so that each engaging pin 202 enters a lock portion 212A of each cam groove 212. Accordingly, the plug 200 is connected to the receptacle 210, and is locked with the torsion coil spring.                Patent Reference 1: Japanese Patent Publication No. 11-339890        Patent Reference 2: Japanese Patent Publication No. 2001-267006        
In the conventional multiphase connector disclosed in Patent Reference 1, when the locking operation is performed as described above, if the sleeve 110 is situated at the initial position, the recess portion 112 engages the projecting portion 104 of the positioning mechanism. That is, the sleeve 110 is restricted with respect to the rotational angle thereof (positioning). When the sleeve 110 is moved forward, the projecting portion 114 moves out from the recess portion 112, so that the sleeve 110 is released from the rotationally restricted state and rotates for locking.
As described above, the sleeve 110 is restricted with respect to the rotational angle thereof (positioning) at the initial position. When the sleeve 110 is moved forward, the sleeve 110 is released from the rotationally restricted state. That is, it is necessary to move the sleeve 110 forward, thereby increasing a total length of the engaging portion 101. Accordingly, it is difficult to reduce a whole size of the connector.
In the conventional multiphase connector disclosed in Patent Reference 2, when the plug 200 engages the receptacle 210, each engaging pin 202 abuts against and is guided with the introducing portion of each cam groove 212, so that the coupling nut 201 rotates by a certain angle. Then, the coupling nut 201 rotates in an opposite direction with a restoration force of the torsion coil spring (not shown) with both ends fixed, so that each engaging pin 202 enters the lock portion 212A of each cam groove 212, thereby locking with the torsion coil spring. That is, each engaging pin 202 enters the lock portion 212A of each cam groove 212 for locking with an urging force of the torsion coil spring. Accordingly, it is necessary to fix the torsion coil spring, and it is difficult to securely lock the connector. Further, when the coupling nut is rotated against an urging force of the torsion coil spring, the coupling nut may be damaged.